The lithium–sulfur (Li–S) battery is a promising candidate for next‐generation high‐density energy storage devices because of its ultrahigh theoretical energy density and the natural abundance of sulfur. However, the practical performance of the sulfur cathode is plagued by fast capacity decay and poor cycle life, both of which can be attributed to the intrinsic dissolution/shuttling of lithium polysulfides. Here, a new built‐in magnetic field–enhanced polysulfide trapping mechanism is discovered by introducing ferromagnetic iron/iron carbide (Fe/Fe3C) nanoparticles with a graphene shell (Fe/Fe3C/graphene) onto a flexible activated cotton textile (ACT) fiber to prepare the ACT@Fe/Fe3C/graphene sulfur host. The novel trapping mechanism is demonstrated by significant differences in the diffusion behavior of polysulfides in a custom‐designed liquid cell compared to a pure ACT/S cathode. Furthermore, a cell assembled using the ACT@Fe/Fe3C/S cathode exhibits a high initial discharge capacity of ≈764 mAh g−1, excellent rate performance, and a remarkably long lifespan of 600 cycles using ACT@Fe/Fe3C/S (whereas only 100 cycles can be achieved using pure ACT/S). The new magnetic field–enhanced trapping mechanism provides not only novel insight but unveils new possibilities for mitigating the “shuttle effect” of polysulfides thereby promoting the practical applications of Li–S batteries.
This content will become publicly available on November 28, 2025
The abundance and environmental friendliness in nature of sulfur (S) make Li–S batteries more attractive in addition to the high theoretical capacity (1675 mAh g−1) and energy density (2600 Wh kg−1) of the batteries. In this study, a bio‐based S cathode with graphene (Gr) coating, capable of effectively suppressing the shuttle effect of polysulfides, is enabled via networking soy protein (SP) and polydopamine (PDA) to form a functional bio‐binder (SP‐PDA). Dopamine self‐polymerization in SP not only generates the interpenetrated network for the bio‐binder but also makes the denatured structure of SP with rich functional groups effective for trapping polysulfides. Meanwhile, the Gr coating with low impedance, and high electronic and ionic conductivity on the cathode surface further significantly reduces polysulfide dissolution. Consequently, the Li–S batteries with the bio‐cathode (SP‐PDA@Gr) demonstrate excellent rate performance and long cycling capacity. In specific, under the current density of 0.5 A g−1at 70% (500 mAh g−1) capacity retention, the cycle life of the Li–S cell with SP‐PDA@Gr cathode is 600 cycles, i.e.,100 times longer than that of the cell with PVDF binder. This study provides a sustainable strategy for enhancing the performance of Li–S batteries through networking natural proteins to form functional bio‐binders.
more » « less- PAR ID:
- 10557238
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Sustainable Systems
- ISSN:
- 2366-7486
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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The shuttling of polysulfides with sluggish redox kinetics has severely retarded the advancement of lithium–sulfur (Li–S) batteries. In this work oxygen-deficient titanium dioxide (TiO 2 ) has been investigated as a novel functional host for Li–S batteries. Experimental and first-principles density functional theory (DFT) studies reveal that oxygen vacancies help to reduce polysulfide shuttling and catalyze the redox kinetics of sulfur/polysulfides during cycling. Consequently, the resulting TiO 2 /S composite cathode manifests superior electrochemical properties in terms of high capacity (1472 mA h g −1 at 0.2C), outstanding rate capability (571 mA h g −1 at 2C), and excellent cycling properties (900 mA h g −1 over 100 cycles at 0.2C). The present strategy offers a viable way through vacancy engineering for the design and optimization of high-performance electrodes for advanced Li–S batteries and other electrochemical devices.more » « less
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